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11.
J M Darby E M Nemoto H Yonas J Melick 《Journal of cerebral blood flow and metabolism》1991,11(3):522-526
Stable xenon (Xe)-enhanced computed tomography is a potentially valuable tool for high resolution, three-dimensional measurement of CBF in patients. However, reports that Xe causes cerebrovascular dilation and increases intracranial pressure (ICP) have tempered enthusiasm for its use. The effects of 5 min of 33% Xe inhalation on ICP (right and left hemispheres) were studied in eight fentanyl-anesthetized Rhesus monkeys after right-sided cortical freeze injury. ICP, CBF, and physiological variables were monitored for up to 6 h postinsult. The preinjury (control) right hemispheric ICP was 8 +/- 5 mm Hg (mean +/- SD) and left hemispheric ICP was 5 +/- 2 mm Hg. Postinjury observations were classified into low (less than 15 mm Hg) and high ICP (greater than or equal to 15 mm Hg) groups. Both right and left ICP values averaged 9 +/- 3 mm Hg in the low ICP group. In the high ICP group, the right ICP was 20 +/- 4 mm Hg and left ICP was 21 +/- 6 mm Hg. ICP was unchanged by Xe inhalation under control conditions as well as in both low and high ICP groups postinjury. Postinjury, the MABP decreased 10-15 mm Hg in the low ICP group and 10-17 mm Hg in the high ICP group 2-3 min after the start of Xe inhalation (p less than 0.05). These results show that 33% Xe inhalation does not increase ICP in fentanyl-anesthetized monkeys but could decrease MABP in stressed states, presumably because of the anesthetic effects of Xe. 相似文献
12.
Kimiaki Hashiguchi Takato Morioka Fumiaki Yoshida Yasushi Miyagi Shinji Nagata Ayumi Sakata Tomio Sasaki 《Seizure》2007,16(3):238-247
OBJECTIVE: To investigate the correlation between scalp-recorded electroencephalographic (EEG) and electrocorticographic (ECoG) activities during ictal periods. METHODS: Simultaneous EEG and ECoG recordings with chronic subdural electrodes were performed in eight patients with partial epilepsy. RESULTS: In two cases where the ictal ECoG discharges originated in deep brain structures such as the hippocampus and interhemispheric surface of the frontal lobe, ictal discharges could not be detected on EEG until they expanded to the cortex of convexity. In four cases, the ictal onset zones were located in the lateral convexity. When synchronous or near synchronous ictal ECoG discharges with amplitudes of 200-2000muV were recorded on more than 8-15cm(2) of cortex, corresponding discharges were recorded on EEG in these four cases. However, in a case of frontal lobe epilepsy, asynchronous ictal ECoG discharges were recorded on 10 electrodes of convexity but no ictal EEG activity was recorded. Furthermore, in two frontal lobe epilepsy cases, ictal EEG discharges did not always reflect the ictal ECoG spike, but occasionally reflected slow background ECoG activity around the ictal discharges. CONCLUSIONS: Multiple factors such as the width of the cortical area involved, amplitude of ictal discharges and degree of synchronization of electrical potentials play important roles in the appearance of ictal EEG recordings, and the relationship between ictal EEG and ECoG is not straightforward. 相似文献
13.
14.
Kazuaki Shimamoto Toru Kita Hiroshi Mabuchi Masunori Matsuzaki Yuji Matsuzawa Noriaki Nakaya Shinichi Oikawa Yasushi Saito Jun Sasaki Hiroshige Itakura 《Hypertension research》2007,30(2):119-123
Hyperlipidemia, hypertension, and diabetes mellitus (DM) are well-established risk factors for cardiovascular disease. We analyzed the cardiovascular events in hyperlipidemic patients with or without DM who were administered open-labeled simvastatin in groups stratified by blood pressure level using data from the Japan Lipid Intervention Trial (J-LIT). Hyperlipidemic patients with DM (n=6,288) had significantly more cardiovascular events than those without DM (n=33,933). The incidence rates of total cardiovascular events in the Non-DM and DM groups were 15.40 and 25.76 per 1,000 patients for the 6-year period, respectively. The relative risk of total cardiovascular events in the DM vs. the Non-DM group was 1.68, and the relative risk was significantly higher in the DM than in the Non-DM group. The relative risks of total cardiovascular events were significantly higher in DM and Non-DM patients whose systolic blood pressure (SBP) was greater than or equal to 130 mmHg compared to that of Non-DM patients whose SBP was less than 130 mmHg, and in DM and Non-DM patients whose diastolic blood pressure (DBP) was greater than or equal to 80 mmHg compared to that of Non-DM patients whose DBP was less than 80 mmHg. In all groups stratified by SBP and DBP, relative risks of total cardiovascular events were higher in DM patients than in Non-DM patients. For patients with hypercholesterolemia and DM, blood pressure should be strictly controlled in order to prevent both coronary events and stroke. These results are in good agreement with the JNC 7 and the ESH/ESC guidelines for DM patients, which recommended that the SBP and DBP be less than 130 and 80 mmHg, respectively. 相似文献
15.
16.
K Nakayama Y Nemoto Y Inoue T Mochizuki S B Soares Jr K Ohata J Katsuyama Y Onoyama K Wakasa 《AJNR. American journal of neuroradiology》1997,18(2):331
Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography. 相似文献
17.
Tsuyoshi Takeda Hiroyuki Ishida Yukio Horiuchi Yasushi Nakao Yutaka Yabe 《Journal of orthopaedic science》1997,2(6):372-377
We examined radiographs of the elbows of the pitching arms of 79 professional baseball pitchers (mean age, 25.1 years; mean
duration of professional career, 4.7 years) and noted the frequency and size of spurs, bone fragments, and intra-articular
loose bodies according to site. The influence of duration of professional baseball career on these osteoarthritic changes
was also investigated. The olecranon tip was the most frequent site of spurs (62/79; 78.5%), and fragmentation of the spur
was detected in 17 joints. The frequency of spurs was also high at the medial margin of the olecranon, the tip of the coronoid
process, the medial margin of the sigmoid notch, the medial margin of the trochlea and the olecranon fossa. In 38 subjects,
spurs were observed at the distal portion of the radial notch of the ulna. However, few pitchers had osteoarthritic changes
in the humeral capitellum or radial head. Intra-articular loose bodies were detected in 4 of 79 joints (5.1%), and bone fragments
were present below the medial humeral epicondyle in 25 of 79 joints (31.6%). Osteoarthritic changes in the elbow joint appeared
to be attributable mainly to traction stress and impingement associated with extension and valgus strain. Significant osteoarthritic
changes were often found in professional pitchers whose careers exceeded 5 years. 相似文献
18.
Kodama Hideya; Fukuda Jun; Karube Hiroko; Matsui Toshihiko; Shimizu Yasushi; Tanaka Toshinobu 《Human reproduction (Oxford, England)》1995,10(8):1962-1967
This study was aimed at assessing the outcome of in-vitro fertilization(IVF) and embryo transfer in patients with polycystic ovariansyndrome (PCOS). The results of IVF and embryo transfer in PCOSpatients (PCOS group, 78 cycles of 26 patients) were comparedwith those of a control group (423 cycles in 202 patients withoutmale factor; age and ovarian stimulation protocol were matched).Although the pregnancy rate per transfer was not different inthe two groups of patients (25 versus 34%, PCOS versus controlgroup), the PCOS group had a significantly lower pregnancy rateper follicle aspiration (19 versus 31%, P < 0.05). A notableresult was a significantly higher incidence of embryo transfercancellations in the PCOS group (22 versus 8%, P < 0.01),which resulted from unpredictable failure of either oocyte recoveryor fertilization. The incidence of unexplained complete failureof fertilization was significantly higher in the PCOS group(18 versus 5%, P < 0.01). These results may reflect a reducedquality of the oocytes in the PCOS group, and there was a subgroupof PCOS patients who repeatedly produced poor results of treatment.Although the ovarian stimulation regimen best suited to PCOSpatients remains to be determined, special care should be takenduring ovarian stimulation, especially when the PCOS patientshad experienced unexplained failure of oocyte recovery or fertilizationin the previous treatment cycle(s). 相似文献
19.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
20.